Definition: A buffer is Like a cache, that is a data area of computer memory(RAM) reserved for temporary storage. For instance, you've probably noticed that you can quickly type a bunch of commands on the keyboard, and then just sit back and watch your computer carry out the commands one after another. This is because the computer stores the keys you pressed in a buffer-after doing one command; it goes back to the buffer to get the next one in line.

Primary memory is also known as main memory or may also refer to "Internal memory." and primary storage. All those types of computer memories that are directly accessed by the processor using data bus are called primary memory. That allows a processor to access stores running programs and currently processed data that stored in a memory location.

Definition: DRAM stands for Dynamic Random Access Memory. DRAM is a technical term for a type of random access memory (RAM) that can retain its contents only for a very brief period (measured in milliseconds) and must, therefore, be continually refreshed by reading its contents at short intervals.

Definition: A disk cache (cache memory) is a temporary holding area in the hard disk or random access memory (RAM) where the computer stores information that used repeatedly. The computer can use it to speed up the process of storing and accessing the information much more quickly from the disk cache than if the information stored in the usual place (which might be on a disk or in a part of the computer's memory that takes longer to access). The term disk cache can also refer to a disk buffer and cache buffer.

Associative Cache: A type of CACHE designed to solve the problem of cache CONTENTION that plagues the DIRECT MAPPED CACHE. In a fully associative cache, a data block from any memory address may be stored into any CACHE LINE, and the whole address is used as the cache TAG: hence, when looking for a match, all the tags must be compared simultaneously with any requested address, which demands expensive extra hardware. However, contention is avoided completely, as no block need ever be flushed unless the whole cache is full, and then the least recently used may be chosen.

The cycle time of a computer is the time required to change the information in a set of registers. This is also sometimes called the state transition time. The register cycle time of a processor is sometimes referred to as the internal cycle time, clock time, or simply cycle time. Main memory cycle time is usually several times the internal cycle time. The internal cycle time may not be of constant value.

Definition: A laser printer (also known as Page Printers as they prints the whole page at once) represent a real technological revolution. laser printer is a type of printer which makes use of a laser beam to produce an image on the drum or you can say that it is a printer that makes use of a focused beam of light to transfer text and images onto paper. It was first developed by Gary Starkweather at Xerox PARC in 1971. Laser printer makes use of laser technology for the printing of copies onto the paper.

The first relatively affordable laser printers were the Apple LaserWriter and the Hewlett-Packard LaserJet. Prices have dropped like a rock and quality is way up since those machines came out, but theunderlying technology remains the same.

The disk controller is circuitry on the computer's motherboard or on a plug-in circuit board that controls the operation of your hard disk drive, floppy disk drives, or both. When the computer wants to transfer data to or from the disk, it tells the disk controller. The controller in turn sends electronic commands to the disk drive making the disk spin and move its magnetic heads to the proper location on the disk. The controller then transfers the data between the computer and the disk drive. The computer's OPERATING SYSTEM and BIOS issue commands directly to the controller to BOOT the computer and to access files stored on the disks.

Firmware is a category or class of memory chips which contain information that is permanent (meaning it isn't erased when you shut off your computer or when the power suddenly goes out on a dark and stormy night). The best examples of firmware are theROM chips in your computer that contain programs installed at the factory. Firmware cannot be altered, per se, but in some cases the whole chip can be completely replaced by a technician when it becomes outdated or obsolete.